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ftx-prog is a Linux command-line alternative to the FTProg utility for FTDI's FT-X series of USB interfaces.


Install some prerequisites

sudo apt-get install build-essential gcc make libftdi-dev

then download, unzip, open a terminal in the unzipped directory and


Don't forget to plug in your FT-X device!


sudo ./ftx_prog

This should give you full details on all the possible options.

Display Current Settings

sudo ./ftx_prog --dump


sudo ./ftx_prog --cbus [cbus pin number] [function]

Sets up configurable CBUS pins with a particular function. Have a look at --help to see all the possible functions, and §7.12 of this application note to see what they all do. Don't forget that the pin numbers are zero based, so --cbus 0 corresponds to the CBUS0 pin.

The most commonly used are:

  • RxLED (pulses low when data is being sent from the host to the USB device)
  • TxLED (pulses low when data is being sent from the USB device to the host)
  • TxRxLED (pulses low when data is being sent either way)
  • SLEEP (goes low when the interface is in USB suspend mode)

Inverting RS232 Signals

FT230X and FT231X only

sudo ./ftx_prog --invert [rs232 pin]

This will invert the polarity of this pin on the chip. So if it was Active High it'll become Active Low and vice versa. You can use --dump to see if the pin is in its default state or not.

The possible pins are:

  • txd The interface's data output pin
  • rxd The interface's data input pin
  • rts Request to Send output pin
  • cts Clear to Send input pin
  • dtr Data Terminal Ready output pin
  • dsr Data Set Ready input pin
  • dcd Data Carrier Detect input pin
  • ri Ring Indicator input pin

Taking RI low (or high when polarity is inverted) for > 20ms will resume the USB host controller from suspend if remote wakeup has been enabled using --remote-wakeup on.


FT200XD and FT201X only

Note: The functionality of these options is completely untested

sudo ./ftx_prog --i2c-slave-address <number>

Sets the slave address of the FT-X on the I2C bus. For instance, --i2c-slave-address 0x22 will restore the slave address to its default value.

sudo ./ftx_prog --i2c-schmitt [on|off]

The I2C pins have schmitt triggers which can be turned on or off.

sudo ./ftx_prog --i2c-device-id <number>

Sets the I2C device ID.

SPI / FT1248

FT220X and FT221X only

Note: The functionality of these options is completely untested

sudo ./ftx_prog --ft1248-cpol [high|low]

The clock on the SPI / FT1248 bus can either be active high (Like SPI Mode 1) or active low (Like SPI Mode 3).

sudo ./ftx_prog --ft1248-bord [msb|lsb]

The bit order on the SPI / FT1248 bus can be either msb first or lsb first.

sudo ./ftx_prog --ft1248-flow-control [on|off]

Turns on flow control when SS_n is inactive.


Note: The functionality of these options is completely untested

sudo ./ftx_prog --rs485-echo-supp [on|off]

Used to enable echo supression if the interface is being used in a RS-485 system.


sudo ./ftx_prog --load-vcp [on|off]

Controls if the Virtual COM Port (VCP) drivers are loaded.

sudo ./ftx_prog --remote-wakeup [on|off]

Allows the interface to be woken up by something other than USB.

Use sudo ./ftx_prog --help to see details of all the command line options.

There are other configuration options that have not yet been implemented in the user interface. Support for the user configurable area in the EEPROM is also a possibility.

Workarounds for FT-X devices


Due to an error in the Silicon Revisions A, B and C of the FT-X series:

The device is put into suspend mode during a transfer of certain data patterns most notable with binary zeros. This can halt the data transfer in certain circumstances and will require the device to be reenumerated to recover. NB. It is the presence of this data pattern on the USB bus regardless of whether the data is intended for the [FT-X] or other devices (e.g. a broadcast) on the bus that forces the suspend state.

This can be fixed by connecting any CBUS pin to ground on the PCB and then configuring it as KeepAwake#. If you were to choose CBUS0 then sudo ./ftx_prog --cbus 0 Keep_Awake will do the configuration.

FT230X and FT231X

In Silicon Revisons A and B of the FT230X and FT231X:

An incorrect value for the VCP driver was programmed into the MTP on some production runs.

This means the Virtual COM Port (VCP) drivers are disabled, preventing the device from appearing as a COM Port on windows. Note: This is untested and may not be true!

To enable the VCP drivers, use sudo ./ftx_prog --load-vcp true.


GPL v2


Bug reports and pull requests welcome!

This project is passively maintained, so there may be no changes for a long time. PRs are more likely to get merged if they are well explained, well commented and match the style of the surrounding code.


Modified for the FT-X series by Richard Meadows 2012

Based upon ft232r_prog, Version 1.23, by Mark Lord. Copyright 2010-2012.


A Linux command-line alternative to the FTDI FTProg utility for FTDI's FT-X series







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